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Central Kazakhstan is frequently referred to as a hypothetical Paleozoic continent Kazakhstania, although its geological structure suggests that in the early Paleozoic it was either a series of island arcs or microcontinents separated by small oceanic basins, each having its own history of development. The cherty and volcanogenic-cherty deposits of the south-western Predchingiz Region and the North Balkhash Region in central Kazakhstan represent an ophiolite rock association with pelagic sediments. The Early-Middle Ordovician conodonts found in the cherty rocks are the only fossils useful for precise dating of the strata and for interpretation of the palaeobiogeographic relations. A low taxonomic diversity is typical of conodonts from these pelagic sediments. Most of them are of the Baltic type, and only some, like Paroistodus horridus and Histiodella tableheadensis, represent other, apparently more warm-water faunal elements. Deep-water conodont faunas from central Kazakhstan are coeval with the Early-Middle Ordovician conodonts from the shelf deposits of southern Kazakhstan, but the latter are taxonomically more diverse and contain warm-water forms (e.g., Juanognathus variabilis, Reutterodus andinus, Serratognathus bilobatus, and Bergstroemognathus extensus). This corroborates the idea that Kazkhstania was closer to the equator, than to the Baltic region in the Ordovician.
The Kowala section situated in the southern part of the Holy Cross Mountains represents continuous sedimentation in almost the same facies across the Devonian-Carboniferous (D-C) transition. The D-C boundary has been identified about two meters above the top of the cephalopod nodular limestone with Wocklumeria. In the transitional deposits of the latest Famennian (Prothognathodus kockeli Zone) several faunally distinct units that correspond to relative sea level changes in the area have been identified. Ostracods are abundant in the Kowala sequence. Their assemblages contain well known index species and new ones of the Thuringian and Entomozoacean ecotypes. A total of 15 probably planktonic entomozoaceans, and 64 benthic species have been identified. Healdia shangquii sp. n. and Mauryella polonica sp. n. are proposed. A major change in the ostracod fauna takes place above the limestone with Wocklumeria within the transitional interval represented by clays and claystones with tuffites in its middle part. Thuringian and Entomozoacean ecotype ostracods disappear and are replaced by more shallow water 'exotic' assemblaged ominated by Healdia, Mauryella and Monoceratina species. In the early Tournaisian rocks Thuringian-, Entomozoacean- and Bairdin-type ostracods reappear with some of the same species as before, and with new Carboniferous index taxa.
A sample taken from a detrital limestone lens, presumed to be allochthonous, within the dark coloured argillaceous limestone of the Early Carboniferous Muhua Formation at the Muhua section, Guizhou, South China, yielded numerous, mostly silicified fossils. Ostracodes, which are the most numerous in the sample, were studied by Olempska (1999). Brachiopods and conodonts are described and illustrated in this paper, but other associated fossils are also noted. Among brachiopods the most common are productides, orthotetidines, spiriferides, and orthides. The productoid gen. et sp. indet. 2, Lambdarina sp., and rhynchonelloid gen. et sp. indet. most probably represent new taxa, but are described in open nomenclature because of inadequate material. Conodonts are indicative of late Tournaisian age. The fossil assemblage is represented by phosphatic and silicified remnants, the latter being originally calcitic. The pattern of silicification resulted generally in preservation of skeletal morphology in great details.
The end of the carbonate sedimentation of the Famennian Wocklumeria limestone in the Holy cross Mts and Sudetes coincides with the disappemance of a high-diversity warm-water assemblage of ammonoids and conodonts with elaborated platform elements. In replacement, a low diversity ammonoid community of Acutimitoceras prorsum and a thin-crown conodont Protognathodus fauna migrated to the afea. When carbonate sedimentation was re-established in the Tournaisian, the new high-diversity ammonoid and conodont faunas represented again almost the whole range of morphologies known from the Famennian. Migrations into the area from unknown sources dominated, with little contribution from the local phyletic evolution. This characteristic ammonoid-conodont community disappeared with the sea-level rise in the Siphonodella crenulata Zone, to emerge at the same time in the North American Midcontinent. The reverse direction of migrations marks the latest Tournaisian Scaliognathus anchoralis event. In yet another cycle of the late Viséan, the new high-diversity faunas were not able to develop as elaborate conch or platform element morphologies as before. In a review of the literature it is shown how the Variscan orogenic activity, progressing towards the Northeast, and glaciations in Gondwana influenced the distribution of late Carboniferous ammonoids in Poland. Conodont taxa Weyerognathus gen. n., Neopolygnathus sudeticus sp. n., and Siphonodella belkai sp. n. are proposed.
Givetian and Frasnian stromatoporoid-coral limestone of the Kowala Formation in the southern Holy Cross Mts is subdivided stratigraphically, and correlated with strata elsewhere on the basis of identified sea-level cyclicity, with support from conodonts and other selected benthic fossils. After the Eifelian hypersaline sabkha phase, an extensive two-step regional colonization of the Kielce Region carbonate platform took place during the Eifelian/Givetian passage interval and the Middle Givetian. At least four deepening pulses resulted in intermittent drowning of the vast carbonate platform and sequential replacement of the undifferentiated Stringocephalus biostromal bank by the Sitkówka bank complex and, subsequently, by the Dyminy reef complex. The reef developed in the central Dyminy belt as result of the early Frasnian accelerated sea-level rise after some period of biotic stagnation near the Givetian-Frasnian boundary. Final demise of the reef resulted from combined eustatic and tectonic movements during the late Frasnian major crisis interval.
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